Pilot study using doxycycline-releasing stents to ameliorate postoperative healing quality after sinus surgery

Poor postoperative healing after sinus surgery is associated with high concentrations of matrix metalloproteinase-9 (MMP-9). The frontal recess is especially vulnerable to restenosis, and frontal sinus stents have been used to overcome this problem. However, the long-term success rate is still controversial and may be poor. In this perspective, we developed doxycycline (DC)-releasing stents, delivering the MMP-9 synthesis-suppressing agent locally to the frontal recess area. We evaluated postoperative MMP-9 levels, bacterial colonization, healing quality, and symptom scores in patients suffering from chronic rhinosinusitis with (CRSwNP) and without nasal polyposis (CRSsNP) (n=10) who underwent functional endoscopic sinus surgery during which the DC-releasing and placebo stents were placed. We found that MMP-9 concentrations were significantly lower at the side of the DC-releasing stent (3,414+/-582 ng/mL) compared with the contralateral placebo stent (9,172+/-2,564 ng/mL) (p<0.05) at month 3 postsurgery. DC stents adequately suppressed bacterial growth compared with placebo stents. Furthermore, the visual analog scale (VAS) for the frontal region was significantly better (mean value 75.1 vs. 52.8, p<0.001) compared with its placebo counterpart. We conclude that compared with placebo stents, DC-releasing stents significantly lowered MMP-9 concentrations and bacterial colonization locally, and improved postoperative healing quality after functional endoscopic sinus surgery, as demonstrated by visual analog scale and ostial closure.